Brain processes underlying the integration of audio-visual speech and non-speech information
Axel H. Winneke & Natalie A. PhillipsDepartment of Psychology, Concordia University
Abstract
We investigated the electrophysiological processes underlying audio-visual (AV) speech perception. Participants performed a categorization task and response times were smallest for AV trials relative to A-alone and V-alone trials. This AV benefit was accompanied by a reduced auditory N1 relative to A-alone trials. This suggests that visual cues, which precede the auditory signal, prime the auditory system which thus processes speech sounds more efficiently. These findings differ from an earlier AV non-speech study (animal sounds and photos), which revealed an AV-related reduction in the visual N1. This indicates that AV speech is processed differently than multisensory non-speech stimuli.
